A wide variety of products include an array of individual devices on a substrate, with the devices addressable or controllable by circuitry on the substrate. Where the individual devices are on the micron scale, e.g., less than 100 microns across, the devices can be considered micro-devices. In general, micro-devices can be fabricated using a sequence of microfabrication techniques, such as deposition, lithography and etching, to deposit and pattern a sequence of layers.
One approach for fabricating a device that includes an array of individual micro-devices is to directly fabricate the individual micro-devices on the substrate which will form part of the product. This technique has been used, e.g., to fabricate the TFT panel and color filter panels of an active matrix liquid crystal display (LCD).
One proposed display panel technology uses an array of LEDs, with individual LEDs providing the individually controllable pixel elements. Such an LED panel can be used for a computer, touch panel device, personal digital assistant (PDA), cell phone, television monitor, and the like.
Although organic light-emitting diode (OLED) panels are in use, an LED panel that uses micron-scale LEDs based on III-V semiconductor technology (also called microLEDs) faces additional problems. In particular, depositing and growing III-V semiconductor microLEDs directly on a final display substrate poses technical and manufacturing hurdles. Moreover, microLED panels are difficult to manufacture in curved or bendable display.